The present invention relates to a circular knitting machine for producing mesh products by means of needles and holding-down plate members which are arranged alternatingly near one another in guiding grooves of a cylindrical needle carrier. The plate members have on their heads a mesh knocking edge and a holding-down notch, and the plate members are arranged displaceably in a longitudinal direction and also turnably under the action of cam parts of an outer cam carrier. The plate members are provided at their rear side with a projection which abuts against a base of the guiding groove and forms a turning region. Finally, the plate members are provided at their front side with a longitudinal control foot and at both sides with a pressing feet.
A knitting machine of the above mentioned general type is disclosed, for example, in the German document DE-OS No. 3,311,361 of the inventor. In this machine the needles and the holding-down plate members are displaced by special control curves so that the plate members with their knocking edges are at least locally displaced during pulling movement of the associated needles, longitudinally and in an opposite direction. Since the plate members perform a combined longitudinal and turning movement, there is an increased danger that the flying fibers and dust penetrating into the guiding grooves are pressed during the plate members movement against the base of the guiding grooves and therefore are compressed there. Due to the irregular and not frequent maintenance of the machines, the compressed fiber layer can affect both the longitudinal movement and the turning of the plate members. This in turn can lead to binding errors in knitting and to destruction of machine parts. The maintenance expenses for the respective circular knitting machines are however very high. For removing the fiber layer which is compressed in the guiding grooves, all cam parts, needles and holding down plate members must be removed from the machine. Finally, the fiber deposit must be removed from each guiding groove with a suitable tool since blowing with the pressure air is no longer sufficient for such removal.